Q: If you were Cory Booker, would a run for governor or senator look more appealing?

BYRNE: Word on the street is that Cory Booker is a great political leader, but not a great administrator. You really need the quality of administration if you’re going to be governor. Not that he can be governor, anyway, because nobody can beat Christie at this point.

KEAN: If I were Cory Booker, I would look at it two ways: First, where can I make the greatest contribution, and second, where would I be happy? If he can answer those two questions, he can make his decision.

Booker hails from Byrne’s Essex County turf in North Jersey, so the ex-governor’s assessments of the Newark mayor’s administrative skills and his chances of defeating Christie are eye-catching.

Both Byrne and Kean, however, have been around long enough to recognize that there are few certainties in New Jersey politics. Two weeks earlier, both governors also asserted that Christie could not be beaten in 2013 but produced examples from their own careers where seemingly impregnable candidates for governor ended up losing.